Graffiti-scrawling has proved to be a serious problem for preservation of public historic buildings, as well as for residential and commercial buildings. This yet-unsolved problem indiscriminately affects the architecture in cities with scrawling that deprive them from beauty, stains, depreciates and damages walls, historic heritage, transport systems, viaducts and other constructions. However, more than merely an esthetic problem, graffiti-scrawling damages the real estate affected, causing financial damages to the Government and/or owners thereof, who have to spend capital for maintenance and restoration of the objects and places damaged by such scrawling.
So far, the market did not make available any formulation that could be resistant to graffiti-scrawling. Once an object had been graffiti-stained, it would not be easy to remove such scrawling, unless one used solvents, sand jets and/or other highly abrasive processes, and it would further be necessary to paint the affected object again.
With regard to the formulations available on the market, there are those intended for imparting protection against graffiti-scrawling on surfaces. However, they are merely palliatives as far as the preservation of the objects is concerned, since the removal of such applied paints is difficult, laborious and expensive, because the cleaning requires the use of chemical products, such as organic solvents and chemical surfactants, which not only attack the environment, but also affect the human health. Besides, with the successive cleanings of the object, the coating film that imparts the desired protection loses its efficacy.
There are still provisional coatings, which do not need solvents for cleaning, only hot water or steam being used for this purpose. However, such coating is removed with the graffiti-paint, for which reason a new application thereof becomes necessary, which generates labor costs for reapplication of such coating, as well as damage to the environment, since harmful raw materials are employed. In addition to all the foregoing, the use thereof is limited, that is, it can only be applied to porous surfaces like stones or apparent concrete.
Further with regard to the anti-incrustation property, it is pointed out that the materials that are commercially available and that exhibit such activity contain heavy metals and/or other toxic substances that bring risks for the marine ecosystem, as well as to the user himself, depending on the case.
Document WO 1991/003522 discloses a cleaning formulation that removes graffiti-scrawling, paints and other coatings, if any, from surfaces. This formulation comprises N-methylpyrrolidone; propylene carbonate; hydroxyl propyl cellulose thixotropic thickening agent; an ingredient selected from the group consisting of diethylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol methyl ether, diethylene glycol ethyl ether and isocetyl alcohol; and a surfactant.
Document PI 9202375-4 discloses a method for protecting surfaces against graffiti-scrawling and cleaning the previously protected surfaces, the method including previous protection of a surface or frontage whatever against graffiti-scrawling by applying enamel or varnish of bi-component aliphatic polyurethane, by application of a mixture of aromatic solvents, such as acetone, thinner and others, with alkaline products such as potassium hydroxide, sodium hydroxide, detergents and soaps.
Document WO 98/21282 discloses a paint composition that includes from about 1 to about 41% by volume of a silicone caulking, from about 1 to about 41% by volume of mineral spirits and from about 18 to about 98% by volume of a paint. The paint composition provides good repellency against graffiti and is not sacrificial in nature.
Document WO 02/16521 discloses a paint containing specific enzymes that remain inactive when applied to a surface coating of the paint formulation until specifically activated through an applying solution, applied subsequently to facilitate the removal of the surface coating. When the solution is applied to the surface coating, the enzymes catalyze the hydrolysis of the binder in the paint or surface coating, for example, by cleaving the ester bonds at positions 1 and 3 of the triglyceride molecules. This enables removal of the coating without damaging or affecting the underlying surface.
Document EP 1529801 discloses a multilayer film (A) comprising a surface layer (L1) and underlying layer (s) (L2), all of them formed from organic polymer (s) and free complexing/chelating agents and mineral fillers, (L1) containing agent (s) (I) to provide removal of the layer by means of a rinsing liquid (B). It also discloses methods of preparing (A), which involves: (1) applying an aqueous emulsion of the polymer to the surface to form a film through coalescence (specifically at room temperature or at the temperature of the use surface), optionally with drying and impregnation with (I); or (2) adding (I) to at least one of two or more separation portions of the polymer emulsion and successive applications of the portions to the surface.
Unlike what is disclosed in the prior art, one of the differentiating aspects of the presently claimed anti-graffiti, self-cleaning and/or non-sticking formulations, as compared with the formulations known from the prior art, is the non-use of a solvent for removing the graffiti-scrawl applied to the object that has been stained therewith.